How Much Is Portrait of Alexander J. Cassatt and His Son Robert Kelso Cassatt Worth?

This is a rare, ambitious double portrait from 1884 depicting Cassatt’s brother, Alexander J. Cassatt—an important American industrialist—and her nephew, Robert Kelso Cassatt. As a prime‑period oil connected directly to the artist’s family and American industrial history, the work carries substantial scholarly and biographical weight. It is frequently reproduced in Cassatt literature and underpins the artist’s narrative as a transatlantic American modernist. Within Cassatt’s oeuvre, major oils—especially large‑scale, resolved compositions from the 1880s—are scarce. This combination of period, scale, ambition, and sitter significance materially elevates the painting above typical portrait offerings and supports upper‑tier valuation.

Large, mature‑period oils by Cassatt are uncommon on the open market and command a premium over her abundant works on paper. At approximately 100 × 81 cm, the painting’s scale sits comfortably within the size band that has historically driven multi‑million outcomes for Cassatt oils when quality is strong. The 1884 date aligns with one of the artist’s most coveted windows, reinforcing both connoisseur appeal and market depth. In contrast to smaller heads or sketch‑like canvases that trade in the low six figures, a resolved, sizable oil from this period rightly benchmarks against prior multi‑million sales for substantial Cassatt paintings.

Cassatt’s most commercially iconic themes remain mother‑and‑child interiors and theater/loge scenes, which tend to outcompete formal portraiture in bidding wars. This double portrait, while biographically important, centers on a male family subject rather than those peak-demand motifs. That dynamic modestly narrows the competitive funnel relative to top ‘mother‑and‑child’ masterpieces or celebrated loge images. Even so, the family connection, scale, and period help offset the subject‑preference discount, keeping the work within a strong upper‑tier band rather than pushing it to the very top of the artist’s price spectrum.

The painting has resided at the Philadelphia Museum of Art since 1959, acquired with the W. P. Wilstach Fund and additional donor support. Such stable, high‑quality provenance and institutional validation materially enhance confidence in attribution, quality, and significance. While museum ownership means the painting lacks a contemporary auction benchmark and sale is unlikely, the curatorial endorsement and continuous public visibility reinforce its stature. In a hypothetical deaccession or private sale context, this pedigree would be a major value driver and a decisive reassurance for top‑tier private and institutional buyers.

No public, detailed condition report is available. For nineteenth‑century oils of this scale, lining, retouching, or varnish issues can meaningfully affect value. A pristine or well‑conserved state would support the upper end of the estimate; conversely, significant structural or aesthetic concerns could compress outcomes. Technical imaging (IR/UV/X‑ray), conservation notes, and a recent condition assessment would be critical pre‑sale. Given the museum setting, responsible care is likely, but until formal reports are provided, condition remains a swing factor in pricing within the proposed range.