Since it was always their grandmothers who cared for the dogs, Lennart realizes it's not possible to keep them. The two brothers are not up for the responsibility of owning two dogs on top of everything they're going through.
https://i.imgur.com/wXTwcpl.png
https://i.imgur.com/K6vk8nY.png
He's working hard on his music now to think about something else.
He's also exercising more, which he finds emotionally helpful.
https://i.imgur.com/KNfj8JU.png
https://i.imgur.com/Ky5bzbW.png
His little brother has sort of locked himself in a shell (or bear suit) as a different way of coping.