Media reports circulating last week said Tyler, 63, had proposed to Brady, 38, after about five years of dating, but neither party publicly announced their betrothal.
EW.com said Tyler's representative confirmed their plans to wed Monday, but said no wedding date has been set.
Tyler was married to clothing designer Teresa Barrick from 1998 to 2006, and to model Cyrinda Foxe from 1978 to 1987. Foxe died in 2002.
The Aerosmith lead singer has four children from his previous relationships, as well as one grandson.
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