Sharing a cot

[ClaireLoux]

My mother has recently purchased a cot for my nephew to use when he stays at her house. I am pregnant and was wondering if it would be okay for my baby to use this cot too.

They would only be using it when they stayed over with my Mum and this would unlikely to be at the same time I have read you should never reuse a mattress but it seems excessive to have mattresses for each of them who would only be used maybe once a week

[kindfriend]

It's fine. No different to nurseries who 'hot cot', changing sheets between babies.
Just make sure the mattress is able to air properly between uses.