Thank you for your question: If a I-485 was properly filed in a correct category, and a child is eligible for a visa (green card) in this category, has a valid and unexpired advance parole/travel document -- then unlawful presence should not be an issue. Under current law, children don't accumulate unlawful presence the same way as adults. Also, under current caselaw, travel under such circumstances is allowed. However, please note (you might want to read official warning in the Instruction to Form I-131 on USCIS website) that admission on advance parole is not guaranteed and can be denied in "discretion" of the CBP officer, and the advance parole can be revoked "at any time". In practice, usually I don't see problems in this scenario. Have a good vacation!
I would like to know if unlawfully present in country accumulate for minors? Child received advance parole after filling I-485 and wants to go to visit grandparents this summer. I would like to know if she will be able to return to US without problems. Thank you!