In the cases in which i petition for my four half-siblings, USCIS is requiring my proofs that my father took care of all of them before they reached they age of 21. after my mother and father separated, he had four children with another woman with whom he lived until shortly before he died (he died in USA after getting his green card through me); he always supported them and lived with them; but never legally divorced my mother; I am sending affidavits from neighbors, school teachers, and hospital birth certificates and bautism certificates, but don't know if this is enough. can i send also a video where appears him and couple and my siblings? after so many years waiting, i don't want uscis to deny the cases. thank you