Do you think my brother is rushing into marriage too fast?

-My younger brother is 22 years old and he just got engaged to this girl he only knew for 4 months!!!! They met at his job where my brother is a home helper to a senior citizen she is one of the senior citizens daughter. He helps her 64 year old mother who recently had a stroke around the house and run arons for her. She's only 28 and has a daughter from her previous marriage. She seems like a nice person but she is a little too old for him I don't think my brother should be rushing into marriage this fast. We had a family dinner last week where he announced their engagement I was shocked to say the least I tried talking to him about it but he wouldn't listen. Divorce seem to run in the family my parents are divorce after 30 years and I recently got divorce so did my sister. He is the youngest and only boy out of 5 girls we are just looking out for him and his well being we love him very much he's our baby brother and don't want to see him get hurt any advice on this matter please? ThanIf you've already talked to him about it, it seems like he already has his mind made up. Just be there for him and be supportive, otherwise he may shut you out.
I fear the same thing about my brother, cuz he just turned 18. To answer your question I for sight a divorce, but who am I to tell you? I'm no psychic.
Let him be- you're his family, not his keepers. You gave your two cents, he knows you don't approve, now let him live his own life and make his own choices. Yes, he might get divorced- but maybe he's genuinely found someone special and will have a long and happy marriage. What he needs right now is people to be happy for him, and share the joy he has founds (or thinks he has found) and get off his back about living his life according to what other people is best for him. I know you mean well, but good intentions have never given free vouchers to pass judgement.