My dentist knew that I collected bird's eggs and asked me whether my collection was growing.
These sentences are quoted from a English-Learning textbook(ビジュアル英文解釈Part I) published in Japan.
The interpretation of "my collection was growing" in the textbook says that, first, someone collected birds eggs, and then, the number of his collection of bird's eggs were increasing. However, I think this sentence can be interpreted in the other way, that is to say, the sentence can also be interpreted as "The bird's eggs in his collection themselves were growing up", not "the number of his collection".
Then, I would like to ask you whether this interpretation of mine is valid or not. Thank you!