If Mom's note on the back is right then the photos were taken in 1986 when Steve turned 40. Both Jo and Jean are ok with that, but I'm still very skeptical. The kids look too old.
I don't want to sound obsessive about this getting the date right, but I've been looking for evidence to corraborate the 1986 theory and the more I look the more I think they were taken later. . .as many as four or five years later in 1990 or 1991. I have nothing conclusive but I'll present the evidence over a number of posts. (We could use more posts!) But first the facts:
1. These are photos found in Mom's stuff. They are not mine.
2. There are 10 photos that appear to be taken near the same time showing two gatherings in the back yard. On the back of one Mom wrote "Steve is 40!"
3. In June of 1986 John died and in August Steve turned 40.
4. Six photos are of a summer party with Carlson's and Steve (see previous post) and it is a party. Notice the water balloons. Also Mom wrote on the back that it was a party when Steve turned 40. Also notice the Carlson's canoe is parked by the house. I'm guessing they're on their way up to or back from The Boundary Waters.

5. Four photos are of a picnic in the backyard with Mark, Lois Ann and kids. Mom's friend Agnes was there too. It looks to me like Mom is serving salmon Mark and Lois Ann probably brought down with them.

5. Why do I say these ten are a batch? First: They were on facing pages of the album book. Second the photo paper is all the same with the same "AGFA" print on the back. Third: Seven of the ten have the identical serial number on the back "1111 N N N+ 1L-1" including photos of Steve's party and Mark and Lois Ann's picnic.
6. What about the other three photos that had a different number on the back? Two were of Heidi Carlson obviously at the same party for Steve. (wearing the same clothes, tossing the same balloons, with the same canoe in the background standing next to the same dad wearing the same T shirt etc.) One was of Heidi Stynsberg obviously at the same salmon feast. (sitting at the same outdoor table with the same table cloth and the same lemon slices on a plate and the same salmon on a tray etc.)