Is my cory gavid?

[Rubberducky]

Hi everyone I'm a bit concerned, I thought my albino cory Snowy was full of eggs but it's been a few weeks now and still no eggs??
Is this normal??
I've done water changes and my tank has lots of nice places to hide plants rocks etc.... she still seems very happy, dashing about the place lol. Sammy my bronze cory does seem to do little dance thing with her and I guessed (since never seen it happen before) that that meant I would see eggs soon, no still nothing???!!!
I'm worried that she may be ill instead.
What do you think?
Ive had Sammy and Snowy for about 18 months.
I have 2 other smaller albino corys and 4 smaller salt n pepper corys that I got about 3-4 weeks ago not sure how old they are when you buy they small from the shop...

 

[Demeter32]

The females will hold the eggs until the environment is right. Adding cooler water usually triggers spawning.

 

[Rubberducky]

Thanks for your advice, so i dont need to worry? I didnt know they could hold the eggs!! I did a quarter tank water change with cool water....nothing.
Then I left the heater off over night (someone else's advice) nothing.
Is there certain foods that might help? I free a variety of foods, flaked, sinking pellets, algae wafers, blood worms some veg ie courgette etc.
Me and my little boy are so excited for these babies!!! My son comes down each morning and examines the tank for eggs!!!