The Collaborative International Dictionary of English v.0.48:
Endearing \En*dear"ing\, a. Making dear or beloved; causing love. -- En*dear"ing*ly, adv. [1913 Webster]WordNet (r) 3.0 (2006):
endearingly adv 1: in an adorable manner; "the toddler behaved adorably" [syn: adorably, endearingly]