Tips on letting LO sleep longer in an empty crib

I let my baby sleep in an empty crib while being swaddled but he doesn’t sleep for long stretches. So I have to pick him up again and again during the night when he fusses. My mil says I should put some bumpers and small cushions so that baby feels secure and can sleep better. But I’m afraid putting stuff in the crib might cause SIDS. Anyone can share some tips, please? Thank you!#firstbaby #1stimemom #bedtime My baby is currently 7 weeks old. UPDATE: My friend alerted me that the empty crib might not be the issue. It might actually be a sleep habit and sleep association issue!