So I’m starting to plan my sons birthday and I decided to do a party but my mom and her bf think…

So I’m starting to plan my sons birthday and I decided to do a party but my mom and her bf think that it’s not the right time because it’s a lot of money and because my son is small and wouldn’t have fun either way. That whatever money I use on the party I can use on him which is a good idea but I was already excited about it and I don’t know what else I would do ? I know my mom would still help me either way but it’s just what she personally thinks...& they aren’t saying to not celebrate it but just do something else besides the party