A teenager who "always looked out for everyone else" died under a train just hours after supporting a friend whose father had died. 

Veronica Romero, 18, of Kelvin Gardens, Croydon, was killed last Monday when she clambered onto the tracks at Wimbledon station after years of fighting depression and bipolar disorder.

She said "goodbye" over the phone to a friend, who heard a train's horn as it approached.

Veronica's family this week paid tribute the "lively and caring" teenager and called for better understanding of the indiscriminate cruelty of mental illness. 

Her brother Juan , 25, said his sister had been upbeat in the days before her death and that life "had started to come together for her".

He said: "It has not quite sunk in yet. She was lively, she seemed happy. She had just got full-time work and was really enjoying it. She was in a new relationship.

"She'd been unemployed, single and had dropped out of college, but then things were starting to look up for her. This is why it's such a shame."

Veronica, who lived with Juan and brother Julio, 22, suffered depression since her childhood and was diagnosed with bipolar disorder after the death of her father Joseph, 55, from colon cancer four years ago. 

Juan, an IT manager, said: "As someone who didn't know much about bipolar disorder, I had to learn about it when she was diagnosed.

"She would go from massive highs to crushing lows. It is a terrible condition. I really do feel for anyone who has it.

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Veronica with brothers Julio, left, and Juan, and aunt Anna Bounaouara

"People don't understand mental health. People can be cold about it. They complain about being late for work when people die like this. 

"Bipolar disorder isn't just something you get over with a bit of help. It's something you have to fight for the rest of your life. 

"It took years for my sister to just find a medication that worked for her.

"And there is not enough funding for mental health. It is really stretched."

He added: "When she was normal, she was a cheerful and friendly person. She would always do her best to get any party started.

"She was very happy, very cheerful, very caring. She always looked out for everyone else.

"That's what she was doing on the day she died. Her friend's dad died two days earlier and she had been to see her to try to support her. She really wanted to help."

Veronica, a former pupil of Carshalton High School for Girls, quit an arts course at Carshalton College earlier this year and had started working at Rift and Co bar in Sutton High Street shortly before her death. 

She was a talented amateur actress and a member of the award-winning Carshalton youth theatre group Savvy. 

Julio said: "We were very close. She shared favourite comedians and music. We went to Reading together to watch Eminem." 

Juan's partner, Gethin Neagle, 26, added: "She always made me laugh. She would say something stupid or silly. She knew how to brighten up people's days.

"It's so sad because she was so young."

For confidential support, contact Samaritans on 08457 90 90 90 or visit samaritans.org