Hadith
Sayyiduna Abu Hurayrah 
sayyiduna ibn abbas
sayyiduna anas and Sayyidatuna
Aaisha [radhiallaahu anha] have reported that;
** ‘When the first fruit of the season used to be brought to Rasulullah
:saw:, he used to kiss it, touch it to his eyes,
recite the following Du’aa and then give it to the smallest child in
his presence:
**
‘Allaahumma kamaa araytanaa awwalahu, arinaa aakhirahu’
Trans: Oh Allah, just as you have shown us the first of it, also show
us the last of it
(These narrations have been recorded by Imaams Abu Dawud in
al-Maraaseel Hadith475-476, Ibnus-Sunni Hadith280; Tabraani in al-Mu’jamus Saghir vol.2 pg.11 and in his Kitaabud-Du’aa Hadith2004, 2005 with slight variations) Haafiz Haythami (RA) has classified the narration of al-Mu’jamus saghir as Sahih (authentic).
** Commentary
The reason for giving it to a child is either because of the similarity
between the two that both are new in the world or because of the
extreme joy that a child experiences through this. (al-Futoohaat
al-Rabbaaniyyah vol.6 pg.235-236)
Hafiz ibn Allaan (RA) mentions that the reason for Rasulullah
:saw: kissing the fruit and touching it to his eyes is
because it has been newly created by Almighty Allah.
Just as Rasulullah used to go out in the rain and open his chest (so that the rain may touch him) and he would say, ‘Verily it (raindrops) recently left my Lord!’. (Sahih Muslim Hadith2080) **