Do I need to buy a new mattress?

[DomesticG0ddess]

For the cot? DS slept on it for almost 3 years, so I am assuming yes.

Yes you might as well as after your dc has slept on it for another 3 years it will be totally worn out .Shame to have to buy a new one later, you might as well start dc off with a new one.

If it's been kept in an attic or garage at any point, you need a new one anyway (possibility of mold spores). But I'd replace a 3 year old one anyway TBH.

I am buying a new one as DD slept on it for 2 years and I know I would worry more about SIDS if I didn't. However plenty of people don't so I guess it's personal choice?

I will get a new one. Thanks.

I didn't - its a very good sprung mattress in good condition, both DD and DS1 slept on it for 2.5 years each and neither were sicky babies, and its been kept indoors not in garage or attic.

When I bought it man in shop said he recommended changing foam mattresses after each child, but if you bought a good quality sprung mattress it would be fine for subsequent children.

Current NHS SIDS advice does not mention new mattresses and anyway difference between getting 2nd hand mattress from someone else and using older siblings mattress.