Husband's ex wife left him a sum of money in her will

I'm really uncomfortable with this. My husband's ex wife passed away. They have one child together and me and my husband are trying for a baby. They have a 17 year old son together. So when we had to read his ex wife's will she left 70% of the money to her son and 30% to my husband... She's very wealthy so 30% is still a huge chunk of money. But when they were together she made him sign a prenup which stated that he take what's his and she takes what's her and she doesn't have to pay alimony. So she covered all her bases so she WOULDN'T have to pay him. And then she just leaves him money. Their son gets the house, any vehicles she has, her business, which that just gave him anxiety until my husband and explained he's not actually gonna be running her business. My husband was in shock because he honestly thought everything was going to his son. This whole thing makes me so uncomfortable

Edit: They were together 13 years.