Is 48 to old to be a mum?

hi guys can i just get your views on this please. my aunt is 48 has just found out she is pregnant for the first time. she tried for over 20years to get pregnant and just wasn't happening so she decided to give up trying and just enjoy the nieces and nephews she was blessed with. However she went to the doctors the other day as she thought she had hit menopause and blood test were run and it Turns out shes around 18 weeks pregnant and in complete shock after trying for all those years. she is so worried because of her age and lots of things can go wrong the older you get and she has got it in her head that this baby will have something wrong with it because of her age. i really feel for her as shes such a great person and deserves this so much but how can we convince her to chill and enjoy and ure her everything will be fine as women much older than her have carried healthy babies.