Sleep deprived

How to deal with sleepless nights.

Well I have been having a problem getting my 7 month old to sleep all night. As I breastfeeding he still feeds atleast twice a night although for the last two nights I have been letting him ' cry it out' ..
It was easy with my first. When she was 6month old I was told by the health visitor that once she's on solids she doesn't need to wake up at night for a feed and if she does its out of habit. So as head strong as I was then, I was desperate for my sleep , desperate for my 8 hours ' beauty ' sleep!! So I set off on this journey of ' controlled crying' . I let my daughter at 6 months, cry at night .. Initially, the first night she cried for 50 mins..it was the most hardest thing I have had to do. But I was so determined and steadfast. I was not going to let a 6 month old 'rule the roost' as my health visitor said. So I carried on and the next night she cried for 30 mins and then 25 mins and then 10 mins and that was it. She's been sleeping 7am-7pm /8am-8pm since then. I triumphed. I succeeded . I got my sleep. But with bloody hard work, determination , ear plugs and crying my eyes out!! At that time I felt like an awful mother, a failure, I felt like I deprived
My child of the cuddles and comfort she needed at that time in her life. But I made sure I made up for it in the day time. Now.. I feel it was the best thing I did. She's got great sleeping habits. She sleeps in the dark on her own in her own bed. She falls asleep on her own too. My beautiful little girl.
However... With my boy 7 month old. It's a different story. He's bigger than she was at 7 months. He eats more and drinks more. He weighs more. I just don't know what to do. I'm craving sleep. I'm shattered everyday and cranky with everyone that comes in my way on a morning. And that's mostly my toddler , my 2 year old.
I have tried the 'controlled crying method' but I seem to give up this time. I worry about my daughters sleep getting disturbed, and the sounds of his cry are heart aching. He seems to have a firmer hold on me than my daughter. I hate it. He definitely 'rules the roost' in my home. I am still going to persevere with the controlled crying method.. I have to detach myself with him during the night. I will just have to make it up during the day. My beautiful baby boy.
Have you had a problem with sleep?
Any ideas will be greatly appreciated.