grow on

absence makes the heart grow fonder

One feels more love or affection for those one loves when parted from them.

grow a pair

To be brave; to show some courage, especially in a situation in which one has so far failed to do so.

grow a set

Synonym of grow a pair.

grow a tail

to be nearly about to defecate, to the point of being unable to completely hold it in

grow apart

To gradually become estranged.

grow cold

To wane; to lose interest or enthusiasm for something or someone; to become disenchanted or to fall out of love with someone.

grow out of

To become too physically large for something, especially clothes.

grow some balls

To be brave; to show some courage, especially in a situation where one has so far failed to do so.