Keeping Up With The Kardashians star Scott was dressed in a grey T-shirt and printed shorts as he took Mason for some frozen yogurt at Menchie's Frozen Yogurt in Calabasas.
This latest photo of Scott comes as US reports suggest he is trying to "prove himself" to Kourtney Kardashian following their split.
A source told E! News: "He's trying to get his life together and that includes getting his family back. He's hoping he and Kourtney can put this behind them. He knows it won't be easy. At the very least, he wants to be friends again."
News of Scott and Kourtney's split emerged last month, with reports suggesting Kourtney ended their relationship due to Scott's excessive partying.
Scott and Kourtney, who are also parents to three-year-old daughter Penelope and seven-month-old son Reign, were pictured meeting up in Beverly Hills two weeks ago.
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