Although this carte de visite is undated, the combination of the baby and the spoon bonnet that Julia is wearing suggests that it may have been taken either early in 1862, after birth of James Wilmer Biddle on 22 Nov 1861 or in early 1863 after birth of Louis Biddle on 12 Mar 1863.
Unknown photographer, carte de visite of Julia Williams Rush Biddle. Philadelphia, ca. 1862-3. 2006.690.