Did I use 的 correctly for 少的孩子？
因为父母不用花钱给很多小孩，他们可以花多一点钱给少的孩子

The ideal sentence:

因为家中孩子不多，父母可以花多一点钱在各个孩子身上 (Because there are few children in the family, parents can spend more money on each child)

If I must minimally edit the original sentence:

因为父母不用花钱在很多小孩身上，他们可以花多一点钱在各个孩子身上 (Because parents don’t have to spend money on many children, they can spend more money on each child)

花钱给小孩 (spend money to the children) is incorrect. It is 花钱在小孩身上 or 在小孩身上花钱 (spend money on the children)

&quot;spend more money on fewer children&quot;

花較多的钱在少些孩子身上