Brief Answer:
Get stool test done and put some nasal drop

Detailed Answer:
Hello

Thanks for asking on this platform

I have gone through the detail and have few queries.
1)How old the babies are?
2)What was the birth weight?
3)What is the present weight or is there gain in weight?
4)Why the babies are put on lactogen(top feed)?
5)The amount of feed you giving per day?

Passing stool once in 7 days or 7 times in a day is common in this age.
I won't get worried if stool is not pellet like or mixed with blood.Change in color of stool can occur in this age and most of the cases it gets back to its normal pattern without any specific treatment.
Still I would like to get routine examination of stool get done to check any malabsorption or any other abnormality.
Continue feeding as usual.Breast feed is the best for babies.Even if top feed is needed check whether it is being prepared properly with appropriate dilution(as per instruction mentioned on the container).
Nasal congestion is also very common in this age and it may cause disturbance in sleep and feeding problem.
Put nasal saline drop(like nasoclear),one drop in each nostril 4-6 times a day to relieve the nasal blockage.
I won't get overly worried if there is no decrease in urinary frequency(it indicates there is no dehydration).
Also adequacy of feeding can be assessed by monitoring the weight of baby.

I hope this helps.
Please get back with the answer so that I better able to help you out.Also let me know if you have any more doubts.

Thanks and regards

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