That's when all the new fawns come out with their folks to meet the other new fawns and to be inspected by Santa.
10 seconds sound clip from the Rudolph the Red-Nosed Reindeer (1964) movie soundboard.
You can hear this line at 00:10:47 in the Blu-ray version of the movie.
Quote context
[...]
- There are more important things than comfort: self-respect.
- Santa can't object to you now.
- Why am I such a misfit? I am just not a nitwit.
- Just because my nose glows, why don't I fit in?
- And so time passes. Christmas comes and goes on schedule, and soon it is April...
- Now, don't worry about your nose, son. Just get out there and do your stuff.
- Remember, you're my little buck.
- Hi. My name's Fireball. What's yours?
- Rudolph.
[...]