Joseph F. Nascimento and his minor daughter Kendall E. Nascimento appeal pro se the district court’s dismissal, pursuant to Fed.R.Civ.P. 12(b)(6), of their civil rights action seeking reversal of a Montana state court decision regarding the custody of Kendall Nascimento. We have jurisdiction pursuant to 28 U.S.C. § 1291. We review de novo the district court’s dismissal and affirm. See H.C. v. Koppel, 203 F.3d 610, 613 (9th Cir.2000) (<HOLDING>); see also Branson v. Nott, 62 F.3d 287, 291
holding that a court should abstain when an exercise of jurisdiction might lead to a parallel federal regulatory review mechanism complicating state administration holding that federal district courts should abstain from interfering with pending state court proceedings holding that courts should only abstain under younger if the state proceedings are coercive and not remedial and citing a number of district court opinions recognizing that the longstanding public policy against federal court interference with state court proceedings generally requires federal courts to abstain from involvement in state criminal proceedings holding that federal courts should apply state substantive law