
    Tamara SWIANTEK, on behalf of M.L.S., Plaintiff-Appellant, v. COMMISSIONER OF SOCIAL SECURITY, Defendant-Appellee.
    No. 14-362-cv.
    United States Court of Appeals, Second Circuit.
    Jan. 8, 2015.
    Kenneth R. Hiller, Amherst, NY, for Appellant.
    David B. Meyers, Special Assistant United States Attorney (Stephen P. Conte, Regional Chief Counsel, on the brief), for William J. Hochul, Jr., United States Attorney, Buffalo, NY, for Appellee.
    Present: ROSEMARY S. POOLER, DEBRA ANN LIVINGSTON and CHRISTOPHER F. DRONEY, Circuit Judges.
   SUMMARY ORDER

ON CONSIDERATION WHEREOF, IT IS HEREBY ORDERED, ADJUDGED, AND DECREED that the order of said District Court be and it hereby is AFFIRMED.

Plaintiff-Appellant Tamara Swiantek appeals on behalf of her minor child, MLS, from 85 the January 29, 2014 decision and order of the United States District Court for the Western District of New York (Ar-cara, /.), which affirmed the determination of the Administrative Law Judge (“ALJ”) that MLS was not entitled to Children’s Supplemental Security Income on the basis that MLS was not disabled. Swiantek argues that the ALJ erred by: (1) concluding that MLS was not markedly limited in the domain of caring for herself; and (2) failing to sufficiently develop the record. We assume the parties’ familiarity with the underlying facts, procedural history, and specification of issues for review.

‘When deciding an appeal from a denial of disability benefits, we focus on the administrative ruling rather than the district court’s opinion.” Moran v. Astrue, 569 F.3d 108, 112 (2d Cir.2009) (quoting Kohler v. Astrue, 546 F.3d 260, 264-65 (2d Cir.2008)). “On appeal, we conduct a plenary review of the administrative record to determine if there is substantial evidence, considering the record as a whole, to support the Commissioner’s decision and if the correct legal standards have been applied.” Burgess v. Astrue, 537 F.3d 117, 128 (2d Cir.2008) (internal quotation marks omitted). “Substantial evidence means more than a mere scintilla. It means such relevant evidence as a reasonable mind might accept as adequate to support a conclusion.” Moran, 569 F.3d at 112 (internal quotation marks omitted). While we employ “a very deferential standard of review,” Brault v. Soc. Sec. Admin., Comm’r, 683 F.3d 443, 448 (2d Cir.2012), we will not hesitate to remand for further findings or a clearer explanation “where we are unable to fathom the ALJ’s rationale in relation to evidence in the record,” Cichocki v. Astrue, 729 F.3d 172, 177 (2d Cir.2013) (internal quotation marks omitted).

To qualify for disability benefits, a child under the age of eighteen must establish that: (1) she is not engaged in “substantial gainful activity”; (2) she has a “medically determinable impairment! or combination of impairments] that is severe”; and (3) these severe impairments “meet, medically equal, or functionally equal the listings.” 20 C.F.R. § 416.924(a)-(d); see also Pollard v. Halter, 377 F.3d 183, 189 (2d Cir.2004). As is most pertinent here, a combination of impairments “functionally equal” the listings if they “result in ‘marked’ limitations in two domains of functioning or an ‘extreme’ limitation in one domain.” 20 C.F.R. § 416.926a. Neither party disputes the ALJ’s determination that MLS was not engaged in substantial gainful activity or that MLS’s bipolar disorder and attention deficit disorder constituted a “severe impairment” that rendered her “markedly impaired” in the functional domain of “[i]n-teracting and relating with others.” See id. Swiantek argues, however, that the ALJ erred in concluding that MLS was not also markedly impaired in the functional domain of “[c]aring for yourself.” See id.

Considering the record as a whole, we conclude that substantial evidence supports the ALJ’s determination that MLS was not markedly impaired in her ability to care for herself. Although Swiantek ' urges that MLS demonstrated her inability to regulate herself during several incidents in which she made suicidal gestures and remarks, the contemporaneous notes of her own treating physicians describe MLS during these events as “attention seeking” or as making a “situational threat” with no evidence of “acute lethality that would warrant acute inpatient care.” After reviewing these treatment notes, the ALJ emphasized the lack of restrictions placed on the claimant by the treatment doctor and observed that MLS has not generally received the type of medical treatment that one would expect for a totally disabled individual. “It is not our function to determine de novo whether [MLS] is disabled.” Pratts v. Chater, 94 F.3d 34, 37 (2d Cir.1996). Accordingly, we accept the ALJ’s determination that MLS’s psychological disorders did not render her markedly impaired in this functional domain, where, as in this case, it is supported by “such relevant evidence as a reasonable mind might accept as adequate to support [the ALJ’s] conclusion.” Moran, 569 F.3d at 112 (internal quotation marks omitted).

We also reject Swiantek’s assertion that remand is necessary in light of the ALJ’s failure to procure an opinion from one of MLS’s treating physicians as to whether MLS was markedly impaired in the domain of caring for herself. “[W]here there are deficiencies in the record, an ALJ is under an affirmative obligation to develop a claimant’s medical history even when the claimant is represented by counsel or by a paralegal.” Rosa v. Callahan, 168 F.3d 72, 79 (2d Cir.1999) (internal alterations and quotation marks omitted). The ALJ’s duty to develop the record reflects “the essentially non-adversarial nature of a benefits proceeding.” Pratts, 94 F.3d at 37 (internal quotation marks omitted); see also Sims v. Apfel, 530 U.S. 103, 111, 120 S.Ct. 2080, 147 L.Ed.2d 80 (2000) (“It is the ALJ’s duty to investigate the facts and develop the arguments both for and against granting benefits-”). However, “where there are no obvious gaps in the administrative record, and where the ALJ already possesses a ‘complete medical history,’ the ALJ is under no obligation to seek additional information in advance .of rejecting a benefits claim.” Rosa, 168 F.3d at 79 n. 5 (quoting Perez v. Chater, 77 F.3d 41, 48 (2d Cir.1996)).

The ALJ in this case based his findings on the psychiatric evaluation of a consultative psychologist who personally examined MLS as well as MLS’s complete medical history and treatment notes, which themselves contained multiple psychological assessments of MLS. Although the Social Security regulations express a clear preference for evidence from the claimant’s own treating physicians over the opinion rendered by a consultative examiner, see 20 C.F.R. § 416.912, this Court does not always treat the absence of a medical source statement from claimant’s treating physicians as fatal to the ALJ’s determination, see Tankisi v. Comm’r of Soc. Sec., 521 Fed.Appx. 29, 33-34 (2d Cir.2013). Given the extensive medical record before the ALJ in this case, we hold that there were no “obvious gaps” that necessitate remand solely on the ground that the ALJ failed to obtain a formal opinion from one of MLS’s treating physicians regarding the extent of MLS’s impairments in the functional domain of caring for oneself. See Rosa, 168 F.3d at 79 n. 5.

We have considered the remainder of Swiantek’s arguments and find them to be without merit. Accordingly, the order of the district court is hereby AFFIRMED. 
      
      . Effective March 26, 2012, the Commission amended 20 C.F.R. § 416.912. Because the AU decision on review was issued on August 15, 2011, those amendments are not applicable to this case. See Lowry v. Astrue, 474 Fed.Appx. 801, 804 n. 2 (2d Cir.2012) ("[W]e apply and reference the version of § 416.912(e) in effect when the ALJ adjudicated [the claimant's] disability claim.’’).
     