im ‧ pres ‧ sion ‧ a ‧ ble /ɪmˈpreʃ ə nəb ə l/ BrE AmE adjective
[ Word Family: noun : ↑ impression , ↑ impressionism , ↑ impressionist , ↑ impressiveness ; adjective : ↑ impressionable , ↑ impressive ≠ ↑ unimpressive , ↑ impressionistic , ↑ unimpressed ; adverb : ↑ impressively , ↑ impressionistically ; verb : ↑ impress ]
someone who is impressionable is easily influenced, especially because they are young:
The kids are at an impressionable age.