Combining sentences with relative clause

I have a question about combining two sentences with a relative clause. Suppose that I have 2 sentences: My son is 35 years old. He has a baby. When I combine them, is it a must to write as "My son who has a baby is 35 years old." or can this sentence be as "My son who is 35 years old has a baby." I know the emphasises and the meanings are different in those sentences, I want to know if it is grammatically correct to combine these sentences in those two ways? Thanks in advance.

My son who has a baby is 35 years old.

My son who is 35 years old has a baby.

Both versions are grammatical but have different meanings.

Also, both use a defining relative clause, which means the speaker has more than one son. We can added a pair of bracketing commas to clarify that the speaker has only one son:

My son, who has a baby, is 35 years old.

My son, who is 35 years old, has a baby.

The first version focuses on the age of the son; the second, on the fact that he has a baby.