Is 70 the age to stop towing

I figured Dad would tow his trailer until he was 90 or more, but he sold it this year (89). Said he had been all the places he wanted to go, too much work otherwise. His sister has a 6 bedroom house and she is alone, so when he visits he can have his own bedroom..

We figured he was done towing a couple years ago, but did not want to admit it. He went out a couple times per year, always something not working right.. he was tired of it.