In this poem Philip Larkin is trying to portray that a baby doesn't need to be wished the regular things, like beauty, when it is born; it needs only to be wished happiness, as that is a gift that will be used throughout all life;
"I have wished you something
None of the others would"
Larkin suggest that only he would have given the baby this, usually at a birth everyone assumes the baby will be happy in later life, the thought often doesn't come across their minds. In this quotation I feel Larkin is speaking as if he knows what he is talking about, or as if he is the parent or close relative of the baby itself, as only they have the time with the baby to wonder what it's future will be like. Using the pronoun "I" implies Larkin is speaking solely; not on behalf of anyone else, but of his own accord.
This links with the second line in this quotation as only he may have thought of it. Larkin uses the verb "have" inferring he has already wished it to the baby, maybe to himself privately, or perhaps he announced it whilst it was a foetus; perhaps because he wanted her to be born happy, unlike most visitors who may say 'You will beÃ¢ÂÂ¦' Larkin presents his gifts as wishes, he "wished" the baby something, as if it was up to the baby itself to fulfill the wish, he can't make her happy; but he can hope that she will be. Again Larkin uses pronouns to speak specifically of one person. "You" suggests that he is talking to the baby, and no one else is in need of knowing. To me it implies that she is the only baby he will...