My son fits a 18 month pretty good, it’s fits him good, not to fitted & not to big on him

He will be 18 months in October right now he’s 14 months. I don’t know if it would be a good ides to move up to 24 months because I’m gonna stock up on some warm clothes for him but then again I don’t want them to big.

I don’t know if he will grow out of 18 month clothing by the time he turns 18 months. Idk what to do because I’m gonna spend around $300 for his clothes and I dontttt want to get a size that’s not gonna end up fitting him in the next few months 😩

What do you mommy’s do in this situation for babies around my sons age?

I forgot to add in the clothes I’m getting are from carters & h&m so I don’t know how the sizing is

I forgot my first born is already 4 so it’s been a while lol