The Land Before Time: A New Adventure is Born
When they were sleeping in sharptooth's
footprint, Cera crawled Littlefoot's arm, and he put it around her neck.
Cera showed great animosity towards Littlefoot throughout the movie. She wouldn't have done this because she loved him, but rather because she was actually scared to be alone.
The Land Before Time II: The Great Valley Adventure
She was the one that came to get Littlefoot
for their meeting, when Ducky could have done it easier.
Cera was the head of the meeting. Ducky had no idea why they were there in the first place, so Cera had to gather everybody. This isn't really out of love, merely she just wants to make sure everybody was there to hear her argument.
The Land Before Time III: The Time of the Great Giving
After Littlefoot fell in the pond, and Topsy
told Cera to come with him, she wanted to be with Littlefoot.
This was mostly more of a friendship thing. Topsy said that she wasn't allowed to play with him, and she felt guilty. That doesn't necessarily convert to love, but more of friendship.
The Land Before Time IV: Journey Through the Mists
Ali shows up, and showed great Jealousy of
her, just because Littlefoot and Ali had interest for each other.
She didn't like Ali in the first place, even calling her "stuck up" because of her distrust towards other species. She was mainly jealous that Littlefoot wanted to play with Ali instead of her, not because she loved him. Also, Ali and Littlefoot didn't love each other. They were just happy to finally meet each other.
The Land Before Time V: The Mysterious Island
I'm pretty sure that they nuzzled once during
it, after Elsie saved Littlefoot and Chomper.
This was more of a hug, and everybody was hugging him because he risked himself to save Chomper. Because the two did not do anything separately, there is no proof that there was any indication of love.
The Land Before Time VI: The Secret of Saurus Rock
She was one of the two that showed concern
when Littlefoot was missing.
Again, everybody was concerned about Littlefoot. She was merely one of the first to call out his name at the time because of the script. Again, this is more of friendship than love.
The Land Before Time VII: The Stone of Cold Fire
She wanted to be right a the front of the vine with Littlefoot.
She was too scared to be in the back, so she wanted to be in front so that somebody from behind could catch her. It had nothing to do with being in love with Littlefoot.
The Land Before Time VIII: The Big Freeze
I'm sure that they snuggled on the first
day it snowed.
As far as I remember, no such scene happened.
The Land Before Time IX: Journey to Big Water
She became more close with Littlefoot, after
the gang thought Mo was killed.
Again, she was jealous that Littlefoot was spending more time with Mo than her, but then she started to realize that she enjoyed being with Mo as well. Again, not really in love with Littlefoot, but merely happy that he still thought of her as a friend.
The Land Before Time X: The Great Longneck Migration
She wanted to go look for Littlefoot when the
others didn't want to.
She wanted to look for him because she had the nightmare about him coming back from his adventure as a hero. She didn't want him to have the glory for himself.
The Land Before Time XI: Invasion of the Tinysauruses
When the tinysauruses were trapped in the
cave, Cera's dad told her to come, and she no, I want to be with
Littlefoot.
She was pissed off at her dad, and the others had left already. Again, nothing to do with love. She also attacked him when he mentioned Tria possibly being her new mother.
The Land Before Time XII: The Great Longneck Migration
She was the only of the gang copying Littlefoot's dance during
"Flip, Flap and Fly"
That could have been the animators deciding to give her the same dance for some reason. That doesn't really justify as love.
The Land Before Time XIII: The Wisdom of Friends
She was the only one that agreed with Littlefoot's wisdoms
after the left valley (except Petrie, but he was just teasing
Littlefoot)
Again, this really doesn't justify love. Maybe she agreed with him more after he kept them alive through the journey, but not through love.
The Land Before Time: The Mysterious Tooth Crisis
When she was sooking in the mud, she acted more playful
around Littlefoot (ex. when she was walking away, she was
swinging her tail back and forth when she knew Littlefoot
was looking)
That was a side effect from being in the mud. She showed no signs of love towards Littlefoot, that was merely her acting strange.