Calf not nursing

Yesterday morning when I was leaving for the day I spotted a cow with a new born calf. So I called my son to go check on it. He did and said he thought it was nursing. When I returned in the afternoon I checked on it and the calf was 100 feet from where it was in the morning and the cow was off feeding. I should add we had 2 inches of snow overnight and it turned to a light rain for the day. The cow returned and the calf tried to nurse for an hour. Never got the teet in her mouth. So I brought the calf to the barn and gave it colostrum and in the morning it drank a quart of milk replacer. Looked like it was doing well and thought I would put it back with the cow in my creep feeder. Watched it for 2 hours and it never got up despite the cow licking a nudging it. Any advice or ideas would be much appreciated.

Calf not nursing