Globally, 45% of under-five deaths are either directly or indirectly attributable to malnutrition, and most of these deaths are in low- and middle-income countries (LMICs). Children are particularly vulnerable in the first 6 months of life. An estimated 4.7 million infants under the age of 6 months are moderately wasted, whereas 3.8 million are severely wasted. Although the children of malnourished women have an increased risk of stunting and wasting, there is little information on this issue. This is a community-based, open-label, multiarm randomized controlled trial that will include parallel group assignments with a 1:1:1 allocation ration in low-income squatter settlements in urban Karachi, Pakistan. The women in the control group (control arm) will receive standard counseling only, whereas the lactating women in the first intervention group (intervention arm 1) will receive two sachets of balanced energy protein (BEP) supplementation per day from enrollment until the infant reaches 6 months of age. The lactating women in the second intervention group (intervention arm 2) will receive the same BEP supplementation as those in intervention arm 1 while their babies will also receive a single stat dose (20 mg/kg orally) of azithromycin at 42 days. The primary outcome will be the relative length velocity from 0 to 6 months by intervention arm. The primary analysis will be intention-to-treat analysis.