Legolas looked at Tauriel as soon as she mentioned to him that he should approach her. His reaction was appeared to be almost unsure, but looking back at the girl, he strided over, internally hoping that his comrade would follow. In truth, he has never interacted with a she-elf in such an affectionate/fond way, with the exception of Tauriel. But, somehow, Yavanna showed something that he had never gotten to see in such a long time. 

She held traits that he could relate to his once-alive mother; that glow that she had, and that kindness, it was an instant reflection. In other words, the young she-elf had enchanted him, overtime, both with her physical and emotional beauty. His thoughts may have distracted him too much, since he found himself standing in front of the girl, when he came back to reality. 

"I'd say we've stumbled upon a love story, brother", Fili noted to Kili, as he watched the scene. Ignoring them, Saeril watched the girl and the Elven Prince.