need help with a gift for my nephews

christening..my MIL bought the cross ..and im the godmother. and SIL bought the outfit..should i offer to pay for it? or is that tacky?

otherwise i need other ideas..how about an i.d. bracelet? do they make them adjustable..i would like him to have it for his communion..or whatever..or do i get another keepsake type thing? any ideas would be appreciated thanks so much