I think the scene where Ennis drops the two girls off at the store where Alma is working happens in mid-winter, as well as the scene where Ennis is mad at Alma because she's going to work, leaving him with the babysitting and dinner serving. In the latter scene, he is wearing a down vest with a red lining, which tells me how he secretly pines for Jack.
Instead of hearts, we see red and white stars on the swingset where Jennie and Alma Jr. are playing. Cut to Jack, who is selling big farm equipment (red) under a sign advertising his father-in-law's business, which has red and white stars on it.
