Synonyms of supportive

2 Syllables
helpful, extra, backup, pitying, spare
3 Syllables
fatherly, assistant, supporting, heartening, reserve, abetting, adjuvant, patriarchal, matriarchal, parental, subservient
4 Syllables
encouraging, sympathetic, collateral, ancillary, fatherlike, secondary, subsidiary, favorable, accessory, appurtenant
5 Syllables
complementary, subordinate, contributory
6 Syllables
recommendatory