Fun little game! Here are my thoughts after finishing the game.
Gameplay: Good platforming is difficult to make, but with some polish you'll get there. There were some technical glitches (jumping when moving up or down a slope didn't always work), and some design decisions that I would do differently (more than one life). As it is it reminded me of early 90s PC platformers :)
Graphics + audio: again- strong early 90s platformer vibe. Graphics were readable and the dog animation was cute :) As for the audio- background music was ok, but adding more sound effects (barks) would be nice.
Theme: I liked how you made the stargazing the reward of the game. Finding my friend at the top of the roof gave me a warm feeling :)
Over all- I had some fun with this one. Keep up the good work (and the kids too)!