Hi Stefanie,
I do typically suggest that guests try to arrive at the theme parks as early as possible in the morning, because crowds tend to be at their lowest in the early mornings. The good news for you is that most of February is not terribly crowded at Walt Disney World. Presidents' Day weekend can get quite crowded, but outside of that, the crowds overall should not be too bad. Therefore, you could probably arrive at a theme park at 1:00 p.m. and still do a fair amount of attractions in the afternoon.
I know that it might sound overwhelming, but you could consider taking the children to a theme park by yourself in the morning. Perhaps you could arrive at a theme park mid-morning, say around 10:00 a.m. Have a plan for the two or three attractions that you and your children will do, get lunch, and by that time, it will be time for your husband to join you. If you do this, you should absolutely consider taking advantage of the
Baby Care Centers at each of the theme parks. These centers provide a great place to feed your little ones, change diapers, and just take a break.
If you decide that you do not want to go to the theme parks alone with your children, I suggest exploring your resort in the morning with your children. I am not sure if you are staying at a Walt Disney World Resort hotel, but if you are, the pool areas are wonderful. Also look on your resort map for playgrounds. The Recreation Guide that you receive when you check in will include a listing of activities such as crafts that your children might enjoy. A final idea for the mornings is to ride some of the transportation. You can take a boat ride between some of the resorts near the Magic Kingdom or Epcot, or you could ride the monorail.
Please do not hesitate to ask if you have any further questions, Stefanie!