A judge might take into consideration a child's familiarity with a school, however the judge would NOT take any of those other things that you mention into consideration...and a judge certain would NEVER take a stepsibling into consideration.
Actually, there is case law in the Alaska Supreme Court where siblings (whether full siblings or not) have been taken into consideration when deciding custody:
Supreme Court of Alaska.
Barry K. McQUADE, Appellant,
v.
Patricia A. McQUADE, Appellee.
No. S-6608.
Aug. 18, 1995.
"The custody investigator further noted that "[t]he sibling relationship in this family is very strong, especially between Jeffrey and his older sister, Lori. It is of utmost importance that this relationship be maintained."
The custody investigator testified that the ideal situation would be one in which Patricia stayed in Alaska so that the parties could continue the shared custody arrangement. The custody investigator further testified that the deciding factor in her custody recommendation was the bond between Jeffrey and his siblings. [FN2] She testified that in her opinion it was in the best interest of Jeffrey to stay with his older siblings."
"1. The superior court did not impermissibly favor sibling bonds over parental bonds.
[4] As to parental bonds, the superior court "carefully considered the love and affection *425 that both parents have" for Jeffrey. Moreover, the superior court considered the custody investigator's report which stated that "Jeffrey loves and cares equally about both parents and appears to be bonded to both." As to sibling bonds, the superior court "considered as an important factor in this case that Jeffrey is bonded to his half brothers and half sister," and found it "essential for Jeffrey to have contact with his half brothers and half sister for his own best interest." Moreover, the superior court considered the custody investigator's report which stated that the sibling relationships were very strong and should be maintained. The superior court also was able to take into account the custody investigator's testimony that the sibling bonds were the deciding factor in her recommendation.
On appeal, Barry argues that the superior court gave too much weight to sibling bonds and not enough weight to parental bonds. Alaska Statute 25.24.150(c)(4) requires the superior court to consider "the love and affection existing between the child and each parent" in determining the best interests of the child. In addition, "[t]his court has often embraced the proposition that it is desirable to not separate siblings in the course of custody disputes." Craig v. McBride, 639 P.2d 303, 306 & n. 9 (Alaska 1982) (the fact that a case involves half siblings has no bearing on "the desirability of keeping the children of the family together") (citation omitted). However, we have declined to adopt a rigid standard for weighing the importance of maintaining sibling bonds in custody disputes, and have instead articulated a more flexible approach:
[C]onsideration should be given to the desirability of not separating the children unless their welfare clearly requires such a course. "
Whether it also applies to a school situation I don't know.
If I broke any rules with the cutting/pasting I apologize. I just wanted to get this information out there.