たって

adverb, noun which may take the genitive case particle 'no'

strongly (hoping or requesting); earnestly

Used with verbs of hoping or requesting, emphasizing a strong desire for something difficult to achieve. Often appears as たっての願い or たっての希望.

• たっての願ねがいで、彼かれに協きょう力りょくを頼たのんだ。

  At his earnest request, I asked him for cooperation.

• たっての希き望ぼうで、その仕し事ごとを引ひき受うけた。

  I took on the job at her strong request.