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"Nothing in my life had ever made me this happy," Carlos Morales, 29, says in an exclusive interview in this week's issue of PEOPLE. Yet a few hours after his four babies were born, everything went horribly wrong as the love of his life, his wife Erica, 36, went into hypovolemic shock and died after severe blood loss. "These babies don't know yet what blessings they have given me. They have given me four reasons to live," Carlos says.
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Carlos Jr., born at 2 lbs., 15 oz., has made it all the way up to 5 lbs., 13 oz. – in large part because he loves to eat ("It's impressive," Dad says). Carlos likes to wrap Carlos Jr. up with his siblings "like a burrito" in their little blankets. A bit quieter than the others, the little guy has a calming influence on his fellow quads. "I have a feeling he's going to be a protective brother," Carlos predicts.
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The smallest baby of the four when she was born at just 2 lbs., 10 oz., Erica (now healthy at more than 5 lbs.) is just like her mother – "she likes her sleep and she likes to relax," Carlos says. That is, until the morning – she's gotten in the habit of screaming her head off. At the hospital, her mother's friends brought over little colored cotton balls so everyone could tell Erica apart from Paisley, her twin (Carlos calls the two of them "twinkies"). Erica's cotton ball is green, her late mother Erica's favorite color.
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Also tiny at birth like her twin, Paisley is now healthy and incredibly alert – "her eyes are always open and she's always looking around. I wonder if she will always stay this awake," Dad shares. She doesn't adore sleep as much as her fellow "twinkie" Erica, but the two of them are both big criers. In fact Paisley, who wears a yellow cotton ball on her ankle, is fond of crying the moment she wakes up.
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Born first at 3 lbs., 4 oz., Tracy (pictured second from the left) is now the biggest quad at 6 lbs., 4 oz. "She is laid-back like me," Carlos says, also seeing elements of her late mother, Erica, like her love of sleep. "She doesn't give me any trouble. Her siblings could learn a thing or two from her!" Tracy is almost always super happy, especially when she has something to eat. During the pregnancy, Erica would call Tracy "poundcake" because she was the first baby to reach a pound in her belly.
For more on Morales and the babies, pick up this week's issue of PEOPLE, on newsstands Friday.