Hello Siena and
to the forums!
Lemon is a cutie! Congratulations
I agree with Aluz that even though the cere is very pale, it still has the noticable purple hue and slighly pearly sheen that may indicate young male
You should have quarantined Lemon away from Crunchy for a minimum of 40 days to prevent the spread of any possible hidden illnesses he may have had. Even if the breeder is great and he seems healthy, budgies are very adept at hiding illnesses and thus he may be hiding something he could spread to Crunch. I would take a look at these threads regarding quarantine:
Also, you should follow certain procedures for slowly introducing two budgies when the time comes so they slowly get used to each other and have a greater chance of being friends.
Here's some links that will help you with introducing two budgies:
Finally, be sure to read through Budgie Articles as well as all the "Stickies" (relevant or informative threads "stuck" to the top of each subforum for easy reference) to ensure you're up to date on the best budgie care and practices!
If you have any questions after reading through anything, please be sure to ask as we'd love to help!
Hope to see you and little Lemon around here!
We'd love to meet your boy Crunchy, too, when you get a chance
I'm glad you've joined us!