YOU SAID:

i am old now and i have grand kids

INTO JAPANESE

私は今歳で、孫がいます

BACK INTO ENGLISH

I am now and have grandchildren

INTO JAPANESE

私は今、孫がいます

BACK INTO ENGLISH

I now have a grandchild

INTO JAPANESE

私には今孫がいます

BACK INTO ENGLISH

I now have a grandchild